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Paroxysmal Kinesigenic Segmental Myoclonus due to a spinal cord glioma

Manuel Marrufo1, Jeffrey Politsky, Shyamal Mehta

  • 1Department of Neurology, Medical College of Georgia, Augusta, Georgia 30912, USA.

Movement Disorders : Official Journal of the Movement Disorder Society
|June 28, 2007
PubMed

Insights

A young man experienced jerking arm movements triggered by sudden actions. Doctors diagnosed a rare spinal cord tumor, leading to the new term Paroxysmal Kinesigenic Segmental Myoclonus.

Area of Science:

  • Neurology
  • Oncology
  • Spinal Cord Medicine

Background:

  • Paroxysmal myoclonus is characterized by sudden, involuntary muscle jerks.
  • Spinal cord neoplasms are rare tumors affecting the spinal cord.
  • Cervical cord astrocytomas represent a subset of spinal tumors.

Observation:

  • An 18-year-old male presented with a 7-year history of left arm jerking movements.
  • These movements were consistently triggered by startling stimuli or sudden actions.
  • Magnetic Resonance Imaging (MRI) revealed an anaplastic astrocytoma in the cervical spinal cord.

Findings:

  • The patient's symptoms represent a novel presentation of paroxysmal myoclonus.
  • This is the first reported case of myoclonus secondary to a spinal cord neoplasm.
  • The condition was termed Paroxysmal Kinesigenic Segmental Myoclonus (PKSM).

Implications:

  • This case expands the known clinical manifestations of spinal cord tumors.
  • PKSM may be an underrecognized paraneoplastic or direct effect of spinal neoplasms.
  • Further research is needed to understand the pathophysiology and management of PKSM.

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